OBJECTIVES: A. Overall objectives: Our overall objective is to define and analyze the steps involved in morphogenesis of the B. subtilis phage 029. This requires analysis of the structure, function and expression of viral genes as well as studies on the assembly of gene products. Goals set for the current year: 1) To evaluate the function of the head fiber protein in 029 assembly. 2) To identify and map all cistrons that code for structural proteins. 3) To define the sequence of gene function during assembly and to further characterize those gene products that appear to have dual or multiple function during morphogenesis. 4) To develop the in vitro complementation system to be used as an adjunct to more conventional techniques employed to study morphogenesis.